Method of cracking oil



2 1927. Jan 5 F. E; WELLMAN METHOD OF CRACKING OIL Filed July 10, 2Sheets-Sheet -l FFW/wf W22 lll Patented Jan. 25,l 1927.

UNITED STATES l`15A-TENT oFFicE."

FRANK E. WELLMA-N, 0F KANSAS CITY, KANSAS, ASSIGNOR TO TEE KANSAS CITYGASOLlNE COMPANY., KANSAS ClllTY, KANSAS, lA CORPORATION OF KANSAS.

METHOD or cnAoKiNe orL..

lAppncation inea July 1o, 1922. serial No. 574,941.

riod Vto, des'tructively affect the container,A

while .at the Same timea high temperature is employed at the point ofapplication of the source, for eiiiciency'in driving in the heatl energyand causing it to penetrate the oil for` cracking purposes. crackingzone is found within a limited area ofl penetration, and it is thereforeimportant to include within it as large a percent- 'age' of the wholebody of oil under treat@ ment as possible, by increasing the heatingsurface.

lin my prior copending application, Serial Number 565,633, filed June 3,1922, .I 'have disclosed an apparatus in which the heating surface islargely increased proportionate ly to the mass of oilunder treatment, byusing a circular series of pipes as containers, with headers andexpansion tanks to prevent foaming, and a rotating burner system inwhich a trailing flame is applied periodically to each pipe. Thecracking zone is thus largely increased, and it is evident that themethod of heating involved might be practiced with various forms ofapparatus, not

necessarily .included within the claims of said application, SerialNumber 565,633.

Hence the purpose of the present application 1- lis to present themethod above referred Loand claim the same Without limitation to caseisa continuation in part thereof.

vBriefly stated, my improved process con- Y of its volume lies withinthe cracking zone ofv direct heat" penetration; the extension being insome symmert'ical of other ligure such that a high temperature sourcemay be The active 'my present invention p .of Fig. 2; anyparticularapparatus- As said method l is disclosed in the foregoingapplication, vthis applied or a high temperature' created, over, 1n orthrough one .circumscribed portion afteranother of the extended bodywith the result thatcrackingenerg'y is driven in und er mostfavorableconditions, atY high eiiiciency, without' destructive action onthe container or containers of whatever nature they may be. f i

Forms of apparatus, both as to the still and as to the heating means,may be varied quite widely without departing from this process. I havecliosen'and shall describe herein the circular pipe still andtherotating burner of my prior copending application, Serial'No.565,633, as the best form known to me at the present time, butcontemplate modifications thereof including circulating coils leadingfrom the upper part of a main sill to the lower part thereof and withtheir turns Varranged in any figure that per. mits a flame or othersource of heat to be applied to them in rotation periodically.' It

rotation. Many other modifications in both the' form of container andthe specific heatingmeans will occur toi those skilled in the art; andall of these are within the sco e of though notspeciliczally claimedherein.

The preferred form of apparatus for practicing my invention isillustrated in the accompanying drawings, in which:

'9 k\li4`ig. l is a vertical section on the line l--l Fig. 2 is atransverse section on the line 2&2 of Fig, l; and

Fig. 3 is a detail` sectional View on an enlarged scale of the burner,its supporting shelf and associated parts.

--.Referring to the drawings, 1 designates a series 'of vertical stillpipes, which may be for example 7 inches in diameter and approximately40 feet in length. These are arranged in a circle, being supportedpreferably at 'their upper ends. 3 is an inner wall or liner ofrefractory material, in the form of Ia frustrum of an inverted cone. t

is the outer furnace Wal-l of the same imaterial in the form of thefrustrumofan up-` right cone. It is to be observed that in cross sectionat any pointthese inner and outer Walls are circular as shown inA Fig.2. At their lower ends, the still pipes 1 are all securedto a ringmanifold 5, from which draW-oif pipes 6 are led Vout through the furnaceWalls 4. At their upperv ends the still pipes are closed by flanged andbolted .but a very small su'rface'for the yielding up of vapor, it isnecessary to provide means for preventing foaming, which I do in theformiof tanks 8th-8. Qlhese tanksare connected to the'still pipes byradial tubes 9-10, the former lying below the normal liquid level andthe latter lying above it. In

addition4 to these connections, the tanks@il and 8, are connected bypipes 11 containing expansion joints 12 With the central equalizing andfeeding tank 13. Below the liquid level this is connected to all of thestill pipes by radial tubes 14. A gauge glass or other convenient formof indicator 15 is provided to show the liquid level in the tank 13.

lhe usual vapor line and make-Yup or feed pipe connections are shown 'at16v and-17, connected to the tank 13, from which the feed of freshmaterial is equalized' to all of th-)still pipes' andthe liquid levelmaintained the saine throughout the system.

The fuel feed and burner mechanism is mai'fked 18, 19, 20, 21, vand 34.The pipe lengths-18, 19 and 21 are double, that is to Say an oil pipe issecured concentrically Within the steam pipe, so that at the burner 34oil and steam are both supplied as determined by suitable valvesconnected `to the supply pipe 18. Centralized v'vithrespect to the stillis a swivel joint 23, the outer section of which is connected to thepipe 19 and is rotated by means of a crown tooth gear 22 and gear 24driven by shaft 25 carrying a sprocket Wheel 26. The pipe section 21drops through an annular slot in the guard plate 20, closing the annularopening 20L in the top of the furnace.- The lower end of the pipe 21(see'Fig. 4), passes through an opening lin the rotating shelf 27 Wherea bend is produced to form a trailing burner arm 28, (see Figs.l 2 and3), which carries a burner composed of a lpair of feeder arms 33 and 35,one carrying oil and the other steam, and a burner head34.

ferai/7e i The arms 33 and 35 are connected to thev inner and the outerpipes, respectively, of the concentric pair 18--19--21 The burner arm 28lies beneath the shelf 27, its' end passingnp through an opening thereinand carrying a T-fitting 32k toA which the 'arms' 33 and 35 are secured.The shelf 27 is annular, pierced With a'ir openings 27a, adjacent theburner, and has depending annular flanges 29 each dipping into liquid 31in an annular trough '30, constituting the top member of anliermetically sealed enclosure 39, which communicates with the outer airthrough piper40, (see'Figs. 1 and 2)v the volume of air supplybeing-regulated bj1-,means such as the damper 41, controlled ashy anoperating rod 42 from thel outside. The chamber 3 9 is of such "size andshape that Workmen may enter it through a suit-- able manhole foradjustment of the burners. When the still is in operation the airchamber and surrounding parts are cool, even the, brick' Work in Walls3' and 4 remaining dark and at a low temperature compared with that ofcracking stills as ordinarily fired.l

The burner system, including the shelf 27, isrotated lat a regular rateof speed by to and bottom gears. At the top, gear 24 1s vcarried onshaft 25, fitted With sprocket 26.

At the bottom the gear 36 meshes with crown teeth around the outer edgeof shelf 27, and is driven through the shaft 37 by motor 50, which alsovdrives the upper shafts 25 through sprocket chain 38 or yequivalentmeans. By suitably relating the Worm sprockets, gears and motor, theentire system is rotated at a uniform speed and Without racking orstrain, the top guard plate sliding around the top of the furnace andpivoting at the joint 23. The shelf 27 may of course be given additionalbearing support in or out of the troughs 30, and the dov`vn pipe 21 maybe duplicated at 180 around the shelf to give a hanging frame, ifdesired. The specific arrangement of 'the burner system is immaterial solong .as it performs the functions described. rllue burner throws itsflameacross the inner sides of the still pipes 1, around which itisrotated at such a rate of speed that any given spot in lany still pipeis Within the directly heated -area during each cycle vof rotation, fora period less than that in which destructive heating would occur. Sincethe air supply to the .annular'combustion space is only by Wayl ofopenings 27, there is no admixture of atmospheric air With the productsof coinbustion, and the. furnace temperature and operatingconditionstherein, are therefore both uniform and eicient. This effects asubstantial saving in fuel, and also produces a more uniform output.

lHaving thus described means for practicingf my invention, the advantagegained b this method of subdivision when combined with rotary or otherperiodic heating, is apparent. rl`he active zone in which suficient heatenergy for cracking penetrates the oil extends inward a limited distancefrom the heated shell of the still or retort. Assuming this to be saytwo inches, and that a six inch pipe be employed, the cross sectionalarea of the zone eiiiciently penetrated is greater than the Varea of thecentral unpenetrated zone. To heat efficiently, a high temperaturesource must be employed, and to prevent destructive effects as Well a'sto uniformly distribute the heat, periodic interruptions of the heatingand cyclicapplications thereof must be produced. IWish'it distinctlyunderstood, however, that the present invention is in no Way limited tothe specific apparatus described, but that it inay be practiced with anyform of apparatus, and with any source of heat, which satisfies therequirements hereinbefore laid dolvn.

In this connection it should be noted that Wherea pipe still or theequivalent is employed, the pipe arrangement or figure adopted must besuch in any case that periodic application of .heat can be made over thesurface of the oil in each pipe in succession. This symmetricalarrangement of units may be for example, in a straight `line with 'anoscillating Haine, in a vertical cylinder with aninwardly pointingradial or tangential Haine, (either the cylinder or.

the fiame rotating), or as in my' prior appli- -cationhereinbeforereferred to, in acircle loil which consists in dividing themain body of oil under treatment into a plurality of connected bodieswhereby the area available for the external applicationof heat isproportionately increased, intermittently and individually heating saidseparated bodies in periodic rotation whereby a degree of heat greaterthan coul; "e withstood if continuously applied may be employed Withoutdestructive action, and dravvlng off the resultant vapors from all thebodies in common While maintaining a common liquid level with extendedsurface vto in the individual bodies.

In testimony whereof I hereunto aiix my signature.

FRANK E. WELLMAN.

prevent foaming

